Vista

Vista allows to analyse complex scenarios with interactions between metrics of different stakeholders.

Flight plan generation and route selection

When airlines select their flight plans between a given origin and destination many different factors need to be considered, such as possible routes available, weather, aircraft performance or time required. Vista uses a data-driven approach analysing historical flight plans, routes between airports and aircraft performances to estimate the cost of operating those different routes.

As shown in the above diagram, the historical analysis of data allow us to generate a pool of two dimensional routes, probability distributions for cruise wind, speed and flight level request and length and duration of climb and descent phases. With this information, for each possible route we can estimate the 4D trajectories that the airline will plan and estimate the total operating cost of these possibilities.

A given flight will, of course, follow only one of the possibilities, so at pre-tactical level, the different flight plans options are prioritised considering their expected direct operating costs (as a function of flight time, fuel and en-route airspace charges). This selection is not deterministic as airlines not always will follow the apparent lest cost route and in Vista we are interested on reproducing realistic flight plan selections options, not the best option!

What if we change the cost of fuel?

Vista is a great tool to analyse the impact of changes of parameters such as fuel cost on the behaviour of the stakeholders in the system. In some areas of Europe, airlines face the possibility of selecting different routes which might incur on different airspace en-route charges and different fuel consumptions and flying time. This leads to trade-offs that can be captured by Vista. An example of one of those regions is western Europe and flights to-from the UK and the Canary Islands. As shown in this image, airlines can select more direct routes using the airspace of France, Spain and Portugal or operate longer routes which benefit from the low airspace usage cost of the Oceanic airspace.

The trade-offs between different metrics for the airlines can be explicitly computed by Vista as shown in the image below for different fuel price scenarios. With higher fuel cost, shorter routes tend to be selected leading to lower fuel usage but higher airspace en-route charges.

As Vista considers multiple stakeholders it is possible to assess the impact of these changes on the demand and expected revenue obtained by the different ANSPs as shown in the following images:

Expected revenue due to en-route charges variation for all of ECAC flights

The figure above shows the expected changes on revenues for the different ANSPs across Europe if changes of fuel price are produced. This illustrates how different parameters are interconnected for different stakeholders in subtle manners that can be captured by Vista: changes on fuel prices represent variations on routes preferences which might have an impact on airspace usage and revenues of the ANSPs!

Over the next decades, EU mobility is expected to progressively evolve from the gate-to-gate focus currently prevalent in the aviation and ATM industry towards a seamless and efficient door-to-door-orientated vision. The paradigm shift from gate-to-gate (hence aircraft centered) to door-to-door (passenger-oriented) is present at virtually all strategic research documents and agendas. The paradigm shift is here to stay. From a passenger perspective, which of the following scenarios create more impact?:

Scenario A): a 8 minute delay in an aircraft arrival time with no connecting passengers

Scenario B): a 5 minute one that prevents a significant number of passengers doing a connection in that airport and subsequently expand their door-to-door trip in more than 10 hours

How can that impact be predicted in terms of time and cost? One of the very first research exercises was the POEM project (SESAR 1- WPE) etc. This project was the original seed of Mercury. Mercury has been afterwards improved, validated and completed in other reseach initiatives for SESAR and European Commission, reaching its current door-to-door status.

What is mercury?

Mercury is a modelling and simulator tool - a framework capable of measuring the performance of the air transport network. It provides a wide range of performance and mobility metrics, capable of describing in detail different air transport scenarios.

Mercury draws on extensive data, drawn from a wide range of industry sources, including airlines, airports and air navigation service providers. Mercury's data models have been demonstrated through over 5 years of research and development, plus industry consultation.

How passenger matter in mercury?

Mercury is the first air transportation network simulator that puts passengers in the centre. Each day of simulation the itineraries of more than 3 million passengers are reproduced. Each passenger has its individual profile, ticket and decisions to make. According to EU regulation 261/2004 passengers are compensated by delay and cancellations. Extended delays, aborted journeys, overnight stays there are all part of the Mercury simulator.

Of course airlines play a major role as well, Mercury incorporates costs models for canonical airline categories. Each of the airline decision of waiting for certain passengers, cancel a flight or even board the passengers and send a ready message even when a ATFCM slot was assigned is taken according to each airline rational cost model.

The secret ingedient: a spice of randomness

There is no way one could develop a simulator like Mercury taking into account every detail in the air transportation system. Some process are just too complex or simply put we do not understand yet. Whilst others are just exogenous factors far beyond the reach of the air transportation system.

But what if we could use a different approach. In Mercury each day of operations is repeated, introducing small variations representing everyday uncertainty and exogenous factors.

Ultimately, small changes lead to completely different day of operations, delays and cancellations. Just similarly to what happens with some chaotic systems, the sensitivity to the initial conditions allow to explore overall trends and stable status, in some cases called emergence.

Interested in reading further info about Mercury? Click here to visit the website.

In Vista, capturing the level of development of the ATM system in the 2035 and 2050 horizons is critical, and we need to ensure that the most relevant scenarios for stakeholders are prioritised during the project. A consultation with relevant expert stakeholders has been conducted to help us with these tasks. The consultation focused on obtaining the experts' view on key aspects of the project, namely: identification of potential missing metrics for the different stakeholders; prioritisation of the metrics generated by the model; identification of potentially missing factors and possible values considered for them; ranking of foreground factors (see previous blog) by relevance; ensuring that none of the factors identified as background factors should instead be considered as foreground; prioritisation of background scenarios and identification of the level of maturity of the system for 2035 and 2050 and, finally, understanding which particular results produced by Vista would be of particular interest to experts and stakeholders. The consultation questionnaire comprised twelve detailed questions and was targeted at high-profile experts in the ATM field.

The result of this activity allowed us to prioritise the metrics and scenarios that will be modelled and ensured that we had not missed any relevant source for regulations or technical evolution of the system. A second consultation is planned in order to review the firsts results obtained with the model. With these consultations, Vista maximises its impact on the community, addressing the topics that are relevant to stakeholders and validating the results obtained.

Another strength of Vista is the inclusion of key stakeholders, not just as consultation body, but as core partners in the project. Vista benefits from such partnership with airlines (SWISS, Norwegian and Icelandair), a FABEC ANSP (Belgocontrol) and airport experts (EUROCONTROL). Dedicated site visits have been carried out in Reykjavik, Oslo and Zurich to further understand the airlines' business models, needs and projected system evolution. These visits also allowed the modelling team of Vista to have first-hand access to the strategic, pre-tactical and tactical management of airlines' operations. This access ensures that the model captures the impact of the different factors as closely as possible to reality. Moreover, the airlines' involvement in the project provides crucial data and validation of preliminary results. Similarly, planned meetings in Brussels and London with Belgocontrol and EUROCONTROL will ensure that the vision of ANSPs and airports are properly considered in the model.

How will different regulatory and business changes affect the KPIs of ATM stakeholders in the 2035 and 2050 horizon? Are the various foreseen changes aligned to obtain improvements in key indicators? Will trade-offs emerge from different policies to be implemented? What is the impact of technology changes on different economic developments?

Vista considers these questions and examines the effects of conflicting market forces on European performance in ATM, through the evaluation of impact metrics on four key stakeholders (airlines, passenger, airports and ANSPs), and the environment. The project comprises a systematic, impact trade-off analysis using classical and complexity metrics, encompassing both fully monetised and quasi-cost impact measures. Vista will model the current, 2035 and 2050 timeframes based on various factors and their potential evolution.

The factors modelled in Vista influence the stakeholders’ choices: prices of commodities and services, regulations from national and supranational entities, and new technologies are all part of a complex socio-economic system that results in evolving business models, passenger choices, etc. These factors are divided between regulatory and business factors. Business factors may affect technology uptake and economic changes. Regulations, on their turn, may act as enablers of the technological and operational changes, e.g., the Single European Sky regulatory framework, or may directly affect the performance of some stakeholders, such as air passenger rights.

The different factors considered have been obtained from a literature review of regulations, projects, technological and operational changes. Concerning the regulations, the different areas of the ATM network and regulations applying to them have been reviewed. Communications and strategies laid down by, or foreseen by, regulatory trends have been used to identify the possible evolution of these regulations. The main source for the business factors are the SESAR projects, in particular, the high-level goals of SESAR described in its Master Plan (Ed. 2015), as well as more precise information related to the SESAR workpackages. The expected impacts of operational sub-packages in SESAR will be used to identify the impact of these on the evolution of KPIs. Some more long-term R&D research activities are also considered, in particular to be used in the 2050 scenarios of Vista. Other business factors include the price of fuel, the business models of the airlines, and changes in demand linked to the socio-economic development of Europe. Regarding the latter, many factors will be considered as closely linked and the diverse possibilities of development will be significantly influenced by outputs such as the STATFOR forecasts.

In the Vista model, regulatory and business factors are classified between foreground and background factors. Background factors are grouped to generate background scenarios onto which the foreground factors will be tested. These background scenarios, identified below, define different possible evolutions for the 2035 and 2050 horizons and have been defined to identify the impact of the technology on different economic development scenarios.

Period

Name

Technology development

Economic development

Current

Current

Current

Current

2035

L35: Low economic, Low Techno

Trajectory-based performance as defined in SESAR

Low economic development

M35: High economic, Low Techno

Medium economic development

H35: High economic, High Techno

Performance-based performance as defined in SESAR

2050

L50: Low economic, Low Techno

M50: High economic, Low Techno

High economic development with an increment on environmental-friendly passengers

H50: High economic, High Techno

Enhanced performance-based performances as defined in SESAR

Examples of foreground factors, the impact of which will be individually assessed, include: regulatory changes on passenger provision schemes, fuel charges, or the introduction of smart ticketing. Foreground factors can also be grouped in higher-level categories to identify the impact of different policies on the scenarios: environmental mitigation policies (e.g., emission scheme and noise pollution regulation), regional infrastructure usage (e.g., airport access, regional infrastructure development), passenger focus modifications (e.g., passenger provision schemes and reacommodation tools) and Single European Sky (e.g., 4D trajectory management, traffic synchronisation, airspace charges). The qualitative impact of the factors, both foreground and background, on each part of the model has been identified.

Vista will necessarily model all ATM phases: strategic, pre-tactical and tactical. Factors will have different impacts on these time scales. The Vista model has been created following these temporal layers. A scenario, defined as an instantiation of foreground and background factors, will be executed by the model. The strategic layer, will use an economic model to balance the strategic demand and capacity of the different elements in the ATM network and schedules will be provided to the pre-tactical layer. The pre-tactical layer will generate flight plans, passenger itineraries and ATFM regulations. These flights and passenger itineraries will be executed tactically using the Mercury model . Mercury model has been developed on previous projects (POEM , ComplexityCosts) and allow the simulation of flights and passengers itineraries obtaining not only traditional flight-centric metric but also passengers focus ones. See our next blog (August) for more information regarding Vista tactical layer. Being a stochastic model the output of the different layers will be consolidated to analyse the results and understand the horizontal and vertical trade-offs identified. Finally, a learning loop will be used to give feedback to the strategic layer on the metrics obtained and, based on the initial expectations of the model, to adjust strategic behaviour. This will ensure that, after several iterations, a stable and realistic realisation of the scenario is obtained.

In order to capture the impact of the different factors on the model and the evolution of the system, dedicated site visits and consultation with experts have been performed (see next blog entry for more details). The Vista approach and methodology was been presented at the 2017 World ATM Congress (7-9 March 2017, Madrid) and at the 2017 ART Workshop (26 April 2017, London).